Storage Spaces is a new feature in Windows 8 that lets you combine the storage capacity of multiple disks into storage “pools”.

Open the Storage Spaces dialogue

You’ll find administration options for Storage Spaces in the Control Panel under System and Security (or simply search for Storage Spaces). At first the only option available will be to create a new pool and storage space. Later, once you’ve created at least one pool, you’ll have options to modify settings and create new spaces.

Choose your drives

Start by choosing which drives you want to incorporate into your pool. You can use a drive that already contains files, but be warned: it will have its entire contents wiped. If possible, pick at least two drives, and ideally three or more. This will enable you to make use of resiliency features, and to get the best performance from your storage spaces.

Configure your storage space

Creating the pool takes just a few seconds. You’ll then be prompted to create your first storage space. Specify a name and a drive letter for it, then choose a resiliency type. It’s not necessary to have multiple identical disks to make use of mirroring, and you can always add more disks to the pool at a later date if space starts to become tight.

Selecting the right size

You can set a maximum size for your space that’s larger than the currently available capacity of the pool. However, once spaces are created they can be expanded but not shrunk, so choose your maximum size carefully. The bottom figure shows how much physical disk space will be needed to accommodate the requested size with resiliency.

Managing your storage space

The main Storage Spaces view now shows many more options: you can create new spaces, extend your pool and view details about the physical disks within it. You can also change the name, drive letter and size of existing storage spaces, but note that you can’t change the resiliency type: that’s set permanently when you create the space.

What happens if a disk should fail?

If one of your drives fails or goes offline you’ll see a warning – but Windows will try to repair the problem automatically, and you shouldn’t lose access to any data. To replace a faulty disk, simply click remove next to its name: if you’re using a resilience method that needs three drives you’ll be prompted to add a new disk before replacing the old one.